What the FDA labels say about taking them together
Dexamethasone and diazepam
Diazepam's FDA label (Valtoco) of June 3, 2026 names dexamethasone in its drug interactions section; the dexamethasone labels PlainMeds reads (4) do not name diazepam. The diazepam label: “Inducers of CYP2C19 and CYP3A4 Inducers of CYP2C19 (e.g., rifampin) and CYP3A4 could increase the rate of diazepam elimination; therefore, efficacy of VALTOCO may be decreased.”
Check it at the source: the dexamethasone FDA label on DailyMed (effective June 6, 2025, Hikma Pharmaceuticals USA, Inc.); the diazepam FDA label on DailyMed (effective August 11, 2026, Waylis Therapuetics LLC).
What does the dexamethasone label say about diazepam?
Dexamethasone's label (effective June 6, 2025) and its 3 other brand-application labels do not name diazepam in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Dexamethasone Intensol), Hikma Pharmaceuticals USA, Inc., effective June 6, 2025 (SPL set b15200fb-1826-472b-a907-e677a272513b), via openFDA; the full label on DailyMed
What does the diazepam label say about dexamethasone?
Valtoco label (Neurelis, Inc, June 3, 2026), drug interactionsInducers of CYP2C19 and CYP3A4 Inducers of CYP2C19 (e.g., rifampin) and CYP3A4 (e.g., carbamazepine, phenytoin, dexamethasone, and phenobarbital) could increase the rate of diazepam elimination; therefore, efficacy of VALTOCO may be decreased.
Source: FDA drug label (Valtoco, NDA211635), Neurelis, Inc, effective June 3, 2026 (SPL set 1a8bcc90-68fa-474d-832c-0df01e825f39), via openFDA
Source: FDA drug label (Valium), Waylis Therapuetics LLC, effective August 11, 2026 (SPL set 260e2041-2bb3-482f-850e-b5d47a7bdbe6), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Dexamethasone | Diazepam | |
|---|---|---|
| Labeled for | Asthma, Eczema (atopic dermatitis), Leukemia, lymphoma and myeloma, Herpes and shingles, Crohn's disease and ulcerative colitis, Multiple sclerosis, Osteoarthritis, Rheumatoid arthritis, Psoriasis, Allergies, Anemia, Pain | Anxiety, Muscle spasms and spasticity |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.193 per tablet 4 mg tablet | $0.0283 per tablet 10 mg tablet |
| Shortage now | In shortage | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once